OREGON STATE UNIVERSITY

Native grasses tapped for revegetation, erosion control

10/24/1997

CORVALLIS - After screening candidates for more than a decade, plant researchers have singled out two populations of blue wildrye, a native grass found throughout the western United States, as excellent choices for use in revegetation and erosion control in the Pacific Northwest.

Researchers have named the two populations, which scientists call ecotypes, "Arlington" and "Elkton" for Arlington, Wash., and Elkton, Ore., towns nearest where the original genetic material was collected.

Arlington was developed by the U.S. Department of Agriculture's Natural Resources Conservation Services (NRCS), the Oregon State University Agricultural Experiment Station and Washington State University's Agricultural Research Center. Elkton was developed by the USDA and OSU.

"We began comparing 128 populations collected from all over western Oregon, western Washington and adjacent areas back in the early 1980s," said Dale Darris, a conservation agronomist for the NRCS's Plant Materials Center at Corvallis.

"The best eight of those were grown in solid stands and further tested for their agronomic performance and maturity differences," he said. "Final evaluations occurred on logging roads, clear-cuts and other upland revegetation sites.

"Both grow well and provide erosion control around wooded areas, particularly those sites that have been recently disturbed by fire, logging or road work," Darris added.

Arlington is especially recommended for the Puget lowlands of western Washington, where it originated. But the grass also has performed well at low elevations in western Oregon, according to Darris.

Elkton is recommended for western Oregon and northwestern California, below an elevation of 2,000 feet.

"Both are tall, erect, medium-coarse, loosely tufted ecotypes of blue wildrye compatible with trees growing in woodlots or along the upper banks of streams and riparian zones," said Darris.

Blue wildrye will take full sun to intermediate shade and grows well in a woodlot where the tree canopy has not completely closed, he noted. Or, it can be used as quick, self-perpetuating cover for erosion control on roadsides or site rehabilitation on burned or cut-over timberland.

Other potential uses for blue wildrye include enhancing wildlife habitat and adding diversity to native plantings, he said. Prior to maturity, the native grass is considered fair to good forage for cattle, horses, deer and elk, but poor for sheep.

"However, the specific palatability and nutritional value of Arlington and Elkton for livestock are not fully established," Darris said.

Arlington and Elkton are short-lived (four to six years) perennials. Arlington has a blue-green appearance and a white waxy coating on the stems. Elkton is grass green, lacks any waxy coating and matures nine to 14 days earlier than Arlington. It also greens up at least a month earlier in the spring.

Darris said both do best on well-drained to marginally drained soil that is moderately coarse to fine textured. Annual rainfall should be more than 25 inches.

"The interest in use of native grasses in the landscape has increased substantially within the past 10 to 15 years," he said. "Blue wildrye is one of the more widely distributed and easy to establish native grasses in our area. However, caution should be taken when considering the use of native grass seed sources originating from environments significantly different from the intended area of use.

"Arlington and Elkton are not necessarily intended to replace local, on-site sources of blue wildrye if such seed is available," Darris said, "especially for ecological restoration plantings."

The recommended drilled seeding rate with Arlington and Elkton for most uses is 10 pounds per acre, he noted.

Certified seed of Arlington blue wildrye is commercially available to the public from seed vendors. Limited quantities of breeder and foundation seed of Elkton are available to qualified growers, as is seed of Arlington, according to Darris.

For more information on where to obtain seed and how to produce or use the two grasses contact Darris at the NRCS Plant Material Materials Center, 3415 NE Granger Ave., Corvallis, Ore., 97330, or Scott Lambert, plant resource specialist, NRCS, Washington State University, P.O. Box 646410, Pullman, Wash., 99164-6410.